Due to the frequently limited amount of exposure of the spine or interior surgical area, spinal implant procedures lend themselves to use of image guidance for surgery. Examples of such image guidance systems include the BrainLAB. System and the Stealth System. The image guidance systems use data from standard CT or MRI scans to build a three dimensional image of the patient's spine. This model is then electronically matched to the patient's anatomy during surgery, allowing the surgeon, in effect, to see through tissue in order to accurately determine the placement of instruments or devices. During the operation, sensitive structures such as blood vessels and nerves, which the surgeon wants to avoid on the way to the anatomical target, can be visualized. In addition, during the operation the surgeon can follow the movements of his or her instruments on the computer screen in real time.
As understood by those skilled in the art, these image guidance systems utilize a computer system with a monitor and two cameras that emit infrared signals, thereby determining the patient's position in the operating room as well as the position of the surgical instruments in relation to the patient's spine. The infrared signals are continuously monitored during surgery using an image tracker receiver that is located in the vicinity of the surgical site.
The present invention comprises a mounting base for mounting an image tracker into a bone of a patient. The mounting base includes a securing mechanism, such as a bone screw, that is inserted through the base and then into the bone. The mounting base also includes at least one projection to further stabilize the mounting base and assist in preventing rotation of the mounting base after attaching the mounting base to the patient. The image tracker array is interconnected to the secured mounting base, thereby providing a secure mounting apparatus that can be used in the immediate vicinity of the patient's surgical site. Thus, in one aspect of the present invention, a device for stabilizing an image tracker in a patient's bone is provided, where the device comprises a securing mechanism and a body, where the body has a first aperture and a second aperture both sized to receive the securing mechanism. In use, the securing mechanism is inserted through the first aperture and the second aperture and inserted into the patient's bone for temporarily stabilizing the image tracker to a patient.
A projection is also preferably used to prevent the device from rotating after inserting the securing mechanism into the patient's bone. Thus, it is a separate aspect of the present invention to provide a mounting base for stabilizing an image tracker in a patient's bone, wherein the device comprises a body having an entrance aperture and an exit aperture and a passageway therebetween. In addition, the device includes means for securing the base to the patient's bone, and wherein the means for securing is sized to be received in the passageway. The device further includes a means for stabilizing the body from rotating. In use, the means for securing is inserted through the entrance aperture, the passageway, and the exit aperture and inserted into the patient's bone for temporarily stabilizing the image tracker to a patient.
A method of using the device is also provided. Thus, it is a separate aspect of the present invention to provide a method of attaching an image tracker to a patient, wherein the method comprises a) inserting a bone screw through a body of a mounting base, the body having an entrance aperture, an exit aperture, and at least one stabilizing projection; b) advancing the bone screw into a bone of the patient; and c) tightening the bone screw into the bone.
Further and more specific advantages and features of the invention will become apparent to those skilled in the art from the following detailed description, taken in conjunction with the drawings.